The water evaporation need to absorb heat .

According to this principle, when the water under the action of gravity by wet curtain flowing downwards, the upside in the corrugated fiber surface will form a water film;

When wet curtain air flowing through the water in the water film can absorb heat from the air after the evaporation, to take away a lot of latent heat, reduce after wet curtain of air temperature, cooling and humidifying cooling purposes.